Electro-optical systems are used for data-handling, and they utilize modulated light as part of the data-handling process. In these circuits, data signals modulate light which is received by a phototransistor which, in turn, provides an output electrical signal. The output signal is utilized in any suitable associated apparatus.
These circuits operate generally satisfactorily; however, the limitation on the speed of response of the phototransistor limits the bandwidth of the circuit.
The present invention provides improved speed of response of a phototransistor.